export function add(a: number, b: number) {
  return a + b
}

export function sub(a: number, b: number) {
  return a - b
}

export function multi(a: number, b: number) {
  return a * b
}

export function div(a: number, b: number) {
  return a / b
}

//向上取整数(小数舍去,正数部分+1)
export function ceil(a: number) {
  return Math.ceil(a)
}

//向下取整数(小数直接舍去)
export function floor(a: number) {
  return Math.floor(a)
}

//四舍五入
export function round(a: number) {
  return Math.round(a)
}

//保留小数
export function fixed(a: number, fixed: number = 0) {
  return a.toFixed(fixed)
}


